Illumination apparatus



-Dec. 26, 1933. R. E. MARBURY ILLUMINATION APPARATUS Filed July 17, 19313 Sheets-Sheet l WITNESSES: I INVENTOR W R6407? Z: Marb ury,

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Dec. 26, 1933. R. E. MARBURY ILLUMINATION APPARATUS Filed July 17, 19313 Sheets-Sheet 2 INVENTOR PavhE/Varb w'y.

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Dec. 26, 1933. R. E. MARBURY ILLUMINATION APPARATUS Filed July 17, 19313 Sheets-Sheet 3 bw mw RN Q INVENTOR 22 E. Md/b my W|TNES%SESJ protect'the gaseous lag will have no deleterious efiect on the cutout.

I Figure 1 Patented Dec. 2 1933 pany, a corpora 1,940,872 I ILLUMINATIONAPPARATUS Ralph E. Marbury, Wilkinsburg, Pa., assignor' to 3Westinghouse Electric 8:;Manufacturing 00111:.

tion of Pennsylvania Application July 17,1931. Serial No. 551,384

My invention relates to illumination apparatus and particularly toillumination apparatus for marking obstructions dangerous to air such ashigh buildings, transmission towers and the like.

It is anaobject of my invention'to provide a marker light forobstructions to air trafiic which will appear. as aball of light andwhich will be readily discernible by'an observer for long distances andat any. angle to the light.'

It is another object oi the invention to utilize neon tubes 'asthepreferable light source in the marker. light because of V coloigdenotingdanger, and because of powerflconsum'ption of such tubes;

their characteristic red the low It isstill another object of theinvention to agedueto' wind, snow, sleet and flying in such manner thatthe maximum light seen by an observer at all angles from the It is 'afurther object of the invention discharge tubes from breakobjects,

may be marker. to connect'the gaseous discharge tubes electrically inseriesin an inexpensive and rugged manner and to also provide forpositively so cutting out tubes which break or. will keep glowing.

fail that the rest of the tubes Y Itis a still furtherobject of the invention to provide 'a cutout across unit which willloads before cuttingthetube out, whi

the neon tubes of the havea definite time lag on overch time It. is anancillary; object of my invention to so arrange the parts of tubes whichfail or are precarious positions. Other objects and advantages ofinvention will become apparent from the following description anddrawings, whereinr in section,

embody one form of my invention; I Fig. 2 is a, bottom themarker lightshown in Fig. 1;

Fig.3 is a view,

injside elevation, of the preferred com is a side elevational view,"partially of a marker light, as constructed to view, looking upward, of

partly in section, and partly truction of -;the cutout utilized. by myinvention;v

Fig. 4 is an end view of the Fig-3;

Fig. 5 is afragmentarycross-sectional a' {spring utilized in the.cutout;

Figs.- 6,- 7 and- 8 are top, side and en respectively, of acontactmember utilize cutout shown in Fig. 3; and

cutout shown in view of:

(1 views, din the I Fig. 9 is a side elevational view, partly insection, ofa marker light, as constructed-topmbody-another form of myinvention.- i

In order to-provide-a bright redball of light which may be seen by anobserver for long dis-. tances, neon-tubes are preferably utilizedbeelized' in.,the unit are preferably-so constructed that the sides thereofare substantiallyparalleland at arfixed distancefromeach other, such asa U shaped tube, such tubes have relatively great strength and the lighttherefrom is concentrated at their outer-portions.

TESi g A If noprovision is made forgcutting outa neon tube connected inseries-with other tubes-when,

failure or breakage occurs, all the tubes will have, their supply ofenergy out off.

Since. neon tubes normally, draw a current of. the order of 30m'illiamperesa film cut out is not applicablebecauserthe. current inthe" system is not suificienttoburn the film away immediately, and theresulting 'sputteringcutout delivers only a part of. the energynecessary tokeep the rest of the. tub'esglfowing. Film, cutouts are,furthermore, not applicable to neon tubesin series because of themomentary highstarting-voltagerequired by such-tubes. Under suchconditions, each @timej the system is: started, the films are burnedslightly, and :will slowly deteriorate and, intime, cut out the tubesentirely, even when'they are in goodcondition. V

.It.- is, therefore, necessary to provide a cutout which will standhigh. starting voltages without .injury; will cut out a tube'in a. shorttime upon failure. or breakage and "will always allowsufii;

cient energy to passto ensurethe glowing of the other, tubes. This isimportant because a :flasha ing. signal ;.may convey .misleadinginformation.

to anairplane pilot.

Inorder to provideacutout to accomplish the aforementionedv desirableresults, a hollow tube, preferably of, a translucent material, isprovided with terminal caps on its endsso-thatit may be held. in clips.An elongated contact member is attached} inside the tube to one of thecaps.-v

Attachedto the other cap and'inside the=tubeisf usually changed in atabs. 7

tabs by suitable means.

a spring which is held in a compressed position by being fastened, by afusible material, to a wire, preferably also attached to the same cap asthe spring.

When the lighting system is energized, the high starting voltage of theneon tube causes an arc to pass between the end of the spring and thecontact member inside the cutout tube, but the fusible material whichholds the spring compressed does not start to melt immediately becauseinsufficient heat is generated by the low current arc. The cutout,therefore, provides a time lag before operating because of overload.This is also an advantage when the supply voltage varies. A neon tubewill drop to normal voltage a few seconds after starting, and the arcingof the cutout will stop.

If a neon tube fails or is broken, the entire line voltage will bethrown upon the cutout. Current flows through the are set up in thecutout to the other tubes until the fusible material is meltedby-th'e'heat of the arc. The spring is then released and forces itselfagainst the elongated contact member, at which time a circuit, havinglow resistance, is establishedthrough the cutout.

In'order that the neon tubes may be protected since the marker light isusually mounted in an exposed position, a canopy isprovidedwhichprotects'the tubes and also supports the conductors from which thetubes receive electrical energy. The canopy and the U-shaped neontubesare so a'ssembledthat the bottoms of the U tubes extend out'farther thanthe edge of the canopy, so that the marker light will be plainlydiscernible to an observer from directly above the light. Enough neontubes are placed in the marker light to give it the'appearance of a ballof red light from a distance.

The conductors for supplying electrical energy to the neon tubes arepreferably solid metal br'ackets'attached to the canopy by insulators,and each bracket is generally provided withtwo open tabs to receive theterminals of the tubes, each tab on one bracket receiving theterminal 1. of a differenttube. "'The'brackets are further provided withapertured ears through which the tubes are inserted when about to beconnected to the brackets. The ears support the tubes approximately inthe middle thereof and decrease the stresses in each tube due to its ownweight, as Well as external forces. The end brackets of the seriesconnection are adjacent but not connected and are provided with only onetab and supporting ear, for reasons hereinafter explained. The bracketsare so disposed that the neon tubes carried thereby point angularly.down to, give maximum spread of light with protection for the tubes. Allthe brackets are provided with'clips fastened thereto above the tabportions for receiving the terminal caps of the cutouts.

'Since the tubes which fail or break must be precarious position,provision is madewhereby the neon tubes may be changed by the operatorwith the use of only one hand. The supporting ears and the tabs on thebrackets are both turned so that, when the bracket is in place, the tabsand ears point angularly downward. The neon tubes are inserted throughthe apertured ears until the terminals are near the open tabs. The earsare above the centers ofthe neon tubes and constitute pivotal pointsabout which the tubes turn and the force of gravity'therefore forces theterminals into theopen The tubes may then be fastened to the The powermay be supplied from a transfoir'h'er housed in a casing, preferablyunder the canopy, or it may be received directly from a high-voltageline through capacitators. The preferable means of connecting the systemto the power supply is to utilize the canopy and the transformer casing,if a transformer is utilized, as a ground. One of the lead wires isconnected to the canopy or casing and the other to the first insulatedbracket; The circuit is completed from bracket to bracket through theneon tubes until the last bracket, which is also grounded to the canopy,is reached. A complete circuit is, therefore, established, with aminimum amount of wiring and a large degree of mechanical strength andadaptability. Referring specifically to the drawings for a detaileddescription of the invention, numeral 1 desig'nates each of a pluralityof electrical gaseous discharge tubes, such as U-shaped neon tubes,provided with terminals 3. A-canopyb, preferably having sloping sides 7,is provided with a support 9 forfastening the entire unit to a structureto be marl're'd. The outer periphery 11 of the canopy 5 does not extendoutwardly a sufficient distance to cover the neon tubes 1, when viewedfrom directly above. The sloping sides '7 of the canopy 5 are providedwith a plurality of' apertures 13 through which threaded bolts 15 oninsulators 17 are inserted and fastened by turning bolt heads 19 tosupport the insulators 17 which are threaded at 23.

The insulators 17 support a plurality of brackets 21, made preferablymetal, such as copper or aluminum, by means of one set of the threadedbolts 15 being disposed with their heads 19 on the outside of thebrackets 21 and extending into the th'readed'insulators 17. The brackets21 are provided with clips 25 fastened thereto by suitablemeans, such asa nut-and-bolt assembly 24, and are adapted to receive terminal caps 31of the cutouts 29. The brackets 21 are further provided with tabs of anelectrical conducting w 33 cut into the metal andeouipped with slots 35.

The tabs 33 are turned inwardlywith respectto the position of thebrackets 21 on the canopy 5;

The slots 35 are'adapted to receive the terminals 3 of the neon tubes-1. e

'Thebrackets 21 are further provided with ears 3'7 which are also turnedinwardly with respect to the position of the brackets 21 on the canopy 5and are preferably provided with resilient gaskets 39in apertures 41 cutor stamped in'the ears 37.

The ears 3'l support the neon tubes 1 above the middle thereof, and, asthe tubes are inserted therein, the force of gravity tends to turn theterminals 3 of the tubes 1 into the slots-35 of the tabs 33, so thatonly one hand need be used'to place the tubes in the marker light. Whenthe tubes are in place, nuts 43 fasten them to the brackets 21. v

The brackets 21a and 21b at the ends of the series-connected system areprovided one tab 33 and one ear 37, of a tube will be held by since onlyoneterminal each of these brackets.

One of the end brackets21b need not beinsulated from the canopy 5, forreasons which will herein erably positioned under the canopy 5-and issup-l ported by the canopy-and the supporting member with only essen ,9.If power is to be derived directly from a hightension' line throughcapacitators (not shown) no transformer need be 1 provided, and thelmarlzer li gh t' takes the" form shown n Fig.9.

In either case'jone side'of thehigh-t en'sion'line from thetransformer'or capacitator (notshown) is preferably connected 'directlyto the canopy, h

anctne other Sideof the line is connected,'through conductor 47, to thesupportingbra'cket 2121 which is provided with an insulator 1'7.

The'current normally flow througheach neon tube and through thebracketsfllfto the next ine'on tube. The last bracket 21b is, groundedto the canopy, and the circuit is thereby "completed.

Cutouts 29 are placed across the terminals 3 'of each tubein' orderthattube failure or breakage shall not cause the uninjured tubes to stopglowing.

The cutout 29, preferably utilized in my invention, consists of atubular member 49,. preferably of a transparent material, so that theconditionof the cutout may be readily ascertained, and is provided withmetal terminal caps 31a and 311) on its ends to engage clips25 on thebrackets 21.

An elongated U-shaped conductor 51 is electrically connected to one ofsaid caps 31a. A spring member 53 is electrically connected to the othercap 31b, and is held compressed by being fastened to the end of a .wire55, also preferably connected to the same end member 311) as thespring'53,by a fusible material 5'7, such as solder. The spring 53 is ofsufficient length, when not compressed, to

press against the elongated U-shaped conductor 51. r v 5 When asufliciently high potential exists across the terminals of any of thetubes 1, an arc is set up between the end of the spring 53 and theconductor 51. If the arc persists, the heat generated thereby melts thefusible material 57 and releases the spring53. The elongated conductor51, and a good electrical contact is attained between them. The tubeacross which the cutout thus operating is positioned is automaticallycut out of the circuit, while the rest of'the tubes receive energy and,therefore, glow.

It will be noted that a certain time delay is present before the fusiblematerial is melted and the cutout operates. During the time interval,however, current is flowing to the other tubes through the are betweenthe spring and the elongated member. It is also apparent that the highstarting voltage for a few seconds of the tube will notharm the cutouts,nor will temporary variations in supply voltage, because of the timelag.

It is apparent that Ihave provided an obstruction marker light whichgives the appearance of a ball of light when observed, and that somelight is emitted as long as one tube is not broken or otherwise fails. Ihave also provided protection for the fragile discharge tubes andcombined therewith an inexpensive and rugged system of supplying powerto the tubes. The inexpensiveto operate, and ease system itself is 7 ofmaintenance is ensured by designing theunit 7 hand in precariouspositions.

the energy source.

. energy,

spring 53 then presses against theplurality of light sources, a two-wiresource of Y electricallenergy, means for connecting'said lightsource'sin s'eriesto the source of electrical energy,

, an electricity-conducting protecting canopyfprovided wane pluralityof; insulators, said 0011- necting means ii'icludingsupportsfor saidlight sources, all but oneofsaidconnecting means being supported by saidinsulators, one sidecof'said 7 source of electrical energy being?grounded to said conducting canopy, and cheer said connecting meansbeing grounded to-said canopy, the .otherside ofsaidsource of'energ'y'being" connected' to one of said connecting mean's'to com pletethe series circuit fromtne light sourc'es to jzfAn'obstruction markerlightcomprising a plurality of light sources, a two-wire source ofelectrical energy, means for connecting said light sources in ,seriesto;the source of electrical an electricity-conducting protecting canopyprovided with a plurality of insulators, said connecting means includingsupports for said light sources, all but one connecting means 'beingsupported by said insulators one side of said source of electricalenergy being grounded to said conducting canopy, and one, of saidconnecting means being grounded to said canopy, the other side of saidsource of energy being connected to one of said connecting means. tocomplete the series circuit from the light sources to the energy source,each light source being provided with means for removing it from thecircuit when excessively high current is present.

3. An obstruction marker light comprising a plurality of elongatedtubular light sources, a source of electrical energy, means forconnecting said light sources to the source ofelectrical energy, aprotecting canopy for said light sources provided with a pluralityofinsulators, all but one connecting means being supported by-said"insulators, said connecting means comprising a bracket of conductingmaterial provided with at least one punched-out tab for terminals forsaid light sources, and being further provided with at least one turnedcar which is apertured'for 120 supporting said light sources.

4. An obstruction marker light comprising a plurality of elongatedtubular light sources, a

source of electrical energy, means for connecting said light sources tothe source of electrical energy, a protecting canopy for said lightsources provided with a plurality of insulators, all but fss oneconnecting means being supported by said insulators, said connectingmeans comprising a bracket of conducting material provided with at leastone punched-out tab for terminals for said light sources, and beingfurther provided with at least oneturned ear which is apertured forsupporting said light sources, said tabs and .ears being constructed topoint substantially downward when said marker is in its uprightoperative position."

5. A marker light comprising, in combination, a support member, atransformer case carried by the support member, a metallic canopy membersecured to the transformer case, a transformer mounted in the casehaving a primary winding for connection to a source of electricalenergy.

and a secondary winding one terminal of which is connected to the canopymember, and a plurality of substantially equally spaced, radially.

extending gaseous discharge tubes connected in series-circuit relationsupported by and insulated from the canopy member having one terminal ofthe series circuit connected to a second terminal oi the secondarywinding and the other terminal connected to the canopy member.

6. A marker light comprising, in combination, support means including amain body member, a plurality of radially extending series circuitconnected gaseous discharge tubes supported by and insulated from thesupport means in substantially equally spaced relationship, one terminalof the series circuit being connected to the support means; and meansfor connecting the remaining terminal of the series circuit and thesupport means to a source of electrical energy.

7. A marker light comprising, in combination,

:support means including a main body member,

g a plurality of substantially equally spacecl'sup portbraoketssecured'to and insulated fromtho support means, each of said supportbrackets'beingprovided with a plurality of upturned apertured portionsand a plurality of upturned

